WASHINGTON: Teaching the history of revolutions has been easy at Harvard this semester. As if to illustrate exactly how these strange historical upheavals work, the university has obligingly staged a revolution of its own. The outside world is under the impression that one of two things has happened at Harvard: Either a reactionary despot has been deposed by faculty freedom fighters, or a bold reformer has been thwarted by vested interests. Most revolutions get written up in these contrary ways.

In reality, revolutions usually begin with rather obscure disputes, like how to pay for a standing army in the colonies. They burst out of political channels only when the grievances against the monarch reach a critical mass and the monarch alienates one too many of his own supporters.

Thus it was at Harvard. The question I found myself pondering last week was whether the same thing is happening in Washington. Could the next president to fall victim to an unruly representative body be George W. Bush?

Like Harvard’s Larry Summers, Bush is a president with a bold vision. Summers wanted to move Harvard science to Allston; Bush wanted to bring freedom to the Middle East. But, also like Summers, Bush has a style problem. Not the abrasive contrariness that alienated professors but a reserve verging on introversion that has cut him off from his own party in Congress.

Ten days ago, I paid a visit to the imposing Russell Building on Capitol Hill, where senators have their offices. What I saw there was a timely reminder of just how much power the Constitution vests in the legislative branch. The senators I spoke with made it abundantly clear that Bush’s political capital — about which he boasted after securing re-election — is all used up. The phrase I kept hearing was lame duck.

It’s not hard to see why. With his approval ratings down to 37%, Bush is now as unpopular as his father was in the year before his defeat by Bill Clinton. As midterm elections approach, the political hunting season has begun. Republicans and Democrats alike are taking potshots at the president as if merely having a lame duck is not enough. They want this duck dead.

Last week they got him with both barrels. The House Appropriations Committee voted 62 to 2 to block the acquisition by Dubai Ports World of the US subsidiary of Peninsular & Oriental Steam Navigation Co., a deal that the president had unequivocally backed. Before Bush could even reach for the presidential veto — a weapon he has never had to use thanks to his own party’s dominance in Congress — Dubai World folded, announcing that it would “transfer fully” P&O Ports North America to “a US entity.”

This is the biggest humiliation Bush has suffered since entering the White House. It is unlikely to be the last.

Grievances in an assembly have a way of multiplying. There was already unease among GOP lawmakers on a number of issues, notably the administration’s insistence that torture, detention without charge and phone-tapping without warrants are all legitimate weapons in the “war on terrorism.”

The idea of Arabs running American ports was the last straw.

But there is a difference between Harvard and Washington. Last year, I listened aghast as Summers abased himself before the faculty with the most abject apology (for his remarks about women scientists) I think I have ever heard. He had forgotten British Adm. Jackie Fisher’s words: “Never apologize, never explain.” Saying sorry was like dripping blood into a pool full of sharks; it only made them hungrier.

This is not a mistake I expect Bush to make; he is likely to be more cussed than contrite. After all, it makes no sense to cast aspersions on the reliability of a Middle Eastern ally like the United Arab Emirates — especially at a time when the US needs all the foreign investment it can get to finance its yawning budget and trade deficits.

Members of Congress should beware of underestimating this president, as others have done in the past. They should remember that a second-term president is not necessarily a lame duck — he is also a man with nothing to lose.

So my guess is that Bush is going to bite back. And the obvious way for him to do this is over Iran. Last Tuesday, Vice President Dick Cheney declared: “We will not allow Iran to have a nuclear weapon.” Remind you of anything? It was Cheney who set the pace four years ago as the administration prepared to confront Iraq, insisting that Saddam Hussein possessed weapons of mass destruction.

And the same sequence of events now looks set to replay itself. The US is going to ask the UN Security Council to impose sanctions if Iran does not halt its programme of uranium enrichment. The other permanent members won’t agree. And then….

Well, when those missiles slam into the Iranian nuclear facilities, don’t say I didn’t warn you. In academic politics, the stakes are relatively low. But where the stakes are high — and they don’t get any higher than American national security — the presidents are harder to roll over. The next time you hear the word “duck” in Washington, my advice would be to do just that. —Dawn/Washington Post News Service